paring, purifying, and refining tallow, wax, and such other substances as are of a greasy or oleaginous nature.

The tallow, or other substance, to be operated upon, having been melted in a leaden or other vessel, incapable of being dissolved by diluted sulphuric acid, a solution, in water, of the article or compound known among chemists under the name of "mineral chameleon," (composed of manganesic or manganic acid and potash, or soda, or other alkaline or earthy base,) is mixed with it. Sulphuric acid, diluted with four or five times its bulk of water, (or any other diluted acid, which has a stronger affinity for the alkaline or earthy base of the chameleon than the manganesic acid, constituting, with the base, the chameleon,) is then gradually added, until the liquor, which separates from the mixture, after it has been well stirred and allowed to stand for a few minutes, is sour to the taste. If preferred, the diluted acid may be mixed with the tallow, or other substance to be operated upon, previous to adding the solution of mineral chameleon. The temperature of the mixture is then raised to about 150o, or from that to 212o, and agitated for an hour; after which the application of heat is discontinued, and the mixture allowed to stand at rest, until the tallow, grease, or other oleaginous substance, rises to and floats upon the surface of the acid liquor, off which, while in a melted state, it may be skimmed, and afterwards applied to the use for which it is required. By this process, the tallow, &c., is bleached or changed in color, according to the quantity of mineral chameleon used, and according to the less or greater tinge of color possessed by the substance before being operated upon.

The patentee states, that mineral chameleon, weighing one-twentieth of the tallow to be operated upon, is sufficient, in solution, to make English tallow, of ordinary quality, white.

The quantity of water to be used in dissolving the mineral chameleon, for bleaching the tallow, or other substance, is not material, but the proportions, which have been found to answer, are twenty or thirty parts, by weight, of water, to one part, by weight, of the chameleon. Instead

of mixing the solution of mineral chameleon with the melted tallow, or other substance, and then adding diluted acid, the solution of mineral chameleon may first have as much of the diluted sulphuric or other acid mixed with it, as is required for the saturation of the alkali contained therein, or as is required to make the mixture sour to the taste. The resulting liquor will be of a red, crimson, or purple color, and this may then be mixed and agitated with the tallow or other substance, which must be kept at a temperature of from 150° to 2120, for an hour, or till the desired whiteness or change of color is produced. The color of the tallow or other substance, may be tested, at intervals, during the operation, by pouring a few drops of it upon a clean cold metallic substance.

If diluted hydrochloric or nitric acid is used, instead of sulphuric acid, the vessel in which the tallow or other substance is to be operated upon, must not be made of lead, as those acids are powerful solvents of that metal; but should be composed of wood, stone, or such other material as hydrochloric or nitric acid will not injuriously act upon.

Instead of using the solution of mineral chameleon, or the compound produced by mixing sulphuric or other acid with the solution of mineral chameleon, as herein before described, the patentee bleaches the tallow or other substance, by the employment of a solution containing the red oxide, or the deutoxide of manganese, or a solution containing manganese, combined with more oxygen than it has combined with it when in the state of protoxide.

The solution to be used in bleaching tallow, &c., according to this part of the invention, is made by putting into a leaden vessel a quantity of sulphuric acid, and diluting it with water till its specific gravity (as found by testing a small quantity reduced to the temperature of 60° Fahr.) is only about 1.70 or 1.66. The operator then sprinkles into it, (while hot,) by little and little, the peroxide, red oxide, deutoxide, or other oxide, (not being the protoxide alone,) of manganese, at the same time stirring the liquor with a leaden rod or stirrer. The quantity of oxide of manganese, which is thus added, should be greater than the

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diluted acid (without the application of other heat than that generated by mixing the acid and water) is capable of dissolving by long digestion. The mixture is then allowed to stand for two or three days, being stirred frequently, to keep the oxide of manganese, as much as possible, in suspension; after which more water is added, and the mixture is stirred till the solution, (which will have acquired a pink or crimson color,) after the excess of oxide of manganese has been allowed to settle, is found to be of the specific gravity of 1.35. The mixture is, after this, repeatedly stirred during the space of three or four days or a week, the specific gravity of the clear liquor being tested, each day, with a hydrometer, and as often as it is found above 1.35, more water is added, until it is reduced to that.When the liquor changes to a deep crimson or claret color, it is fit for use.

The proportions which the patentee has found to answer, in preparing this solution, are one hundred and sixty pounds of good commercial peroxide of manganese to each five hundred pounds of concentrated sulphuric acid, and the requisite quantity of water. Other acids may be used instead of, or along with, the sulphuric acid.

The tallow, or other substance, is now melted in a leaden or other vessel, (if not already in a fluid state,) by the introduction of steam or otherwise; and when its temperature is about 120° Fahr., or from that to 130°., the crimson or claret-colored liquor or solution is added by degrees. The tallow is kept stirred whilst the solution is being poured into it, and this stirring is continued for an hour, or till the tallow, or other substance, is sufficiently bleached, which can be ascertained, as before stated, by pouring a few drops upon a clean cold metallic substance.

When it is bleached to the satisfaction of the operator, the temperature is raised to 155o or 160°, and the stirring being then discontinued, the liquor will settle in the course of a few hours, and the melted tallow, or other substance, will float upon its surface, from which it may be skimmed or otherwise removed, and applied to such purposes as it may be required for. A ton of good English

tallow may thus be made white, by an expenditure of one hundred and forty quarts of the crimson or claret-colored liquor, of the specific gravity 1.35. The quantity required for the bleaching of other substances besides tallow, is more, or less, according to the depth of color possessed by the substance before being operated upon.

When the liquor is mixed with the melted tallow, the mixture has at first a pinkish or muddy crimson hue, produced by the liquor being in a state of mechanical suspension or mixture in the tallow; but this vanishes as the tallow becomes bleached, and the liquor is afterwards found to have lost its crimson or claret color.

The residuary liquor, from which the bleached tallow has been removed, is used in preparing and purifying or "rendering" other tallow or greasy substance. The tallow, greasy substance, or fat, as brought from the butchers or other source, that is, before being separated from the cellular membrane, &c., which accompany it when obtained from the carcase it is derived from, is put into the vessel containing the residuary liquor, and heat is applied by the introduction of steam, or in any other convenient manner. By this means the membrane is dissolved, or the cells burst; and when the contents of the vessel have been kept at about the temperature of 160°, or from that to 2120, for an hour or two, the whole or greater part of the tallow or grease is liberated from the cells. Then, on the steam being shut off, and the mixture allowed to settle, the prepared or rendered tallow will float upon the surface of the liquor, and can then be removed into another vessel, for the purpose of being bleached, or may be disposed of in any other way.

The patentee states, with respect to the operation just described, that the liquor resulting from the bleaching of a ton of tallow, is sufficient to complete the preparing or rendering of a ton of fat, fresh from the butcher's. If thought desirable, fat may be prepared and bleached at one operation, by mixing it in the state in which it is received from the butchers, with the requisite quantity of the crimson or claret-colored liquor, and heating the mix

ture to the temperature of about 1500 or 160°, at the same time stirring it well; after it has been kept at this heat for an hour or two, the temperature is raised to about 212° and maintained at that, for a short time, if it should be found requisite. After the fat or tallow, thus operated upon, has become clear, by standing for a time, it may be removed from the surface of the liquor. In this operation, it is requisite to use somewhat more of the crimson or claretcolored liquor than is required for bleaching tallow that has been previously prepared or rendered.

The utensils with which the mixtures of tallow, &c., and chemical ingredients, are to be stirred or otherwise brought into contact, and the vessels used, should be of lead, or of wood, covered with lead, provided that sulphuric acid is the acid used in the preparation of the solution; but when the solution is formed by the aid of any other acid, the utensils and vessels should be of wood, stone, or other substance, not capable of being acted upon by the acid in the solution.

With regard to the improved processes above described, the patentee claims the application of a solution of mineral chameleon or compound of manganesic or manganic acid and potash, or soda, or other alkaline or earthy base, to wax, tallow, or other greasy or oleaginous substance, in a melted, fluid, or softened state, by mixing the same therewith; and the previous or subsequent application of sulphuric acid, (or other acid having a stronger affinity than the manganesic acid for the alkaline or earthy base of the chameleon,) to the said mixture, for the purposes of bleaching and changing the color of the tallow, or other substance.

And he claims, for the same purposes, the application (by mixing) to melted, fluid, or softened wax, tallow, grease, or oleaginous substance of a solution or mixture, formed by adding sulphuric acid, or such other acid as just alluded to, to a solution of the mineral chameleon, previously to either of them being added to the substance to be operated upon. He also claims the application of a solution, (made by the aid of acid,) of the red oxide or the deutoxide of manganese, or a solution containing manganese, combined with more oxygen than it has combined with it when in the state of

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